不同阶段生长肥育猪可消化赖、蛋+胱、苏、色氨酸平衡模式研究

Two nitrogen balance trials after partial deletion of dietary amino acids(AA) were conducted to investigate the ideal balance patterns of dietary digestible lysine(Lys),sulphur containing amino acid(SAA),threonine(Thr)and tryptophan(trp)for the growing(35 60kg)and finishing (60 90kg) pigs.Eighteen Yorkshire × Landrace crossbred castrates were employed for the trials.Six isoenergetic diets based on corn,soybean meal and corn gluten meal were prepared for each trial.They were basal diet(BD)with 16 1% and 14 9% crude protein(CP)for each stage,25% low CP diet(s) supplemented with all the four (positive control,PC)or with three of the four AAs to have an equal digestible AA content,except the examined one which was 25% lower than that in BD.The result showed that the ideal amino acid pattem expressed on digestible basis was Lys 100,SAA 49,Thr 72,Trp 19 for growing stage and Lys 100,SAA 34,Thr 64,Trp 23 for finishing stage of pigs.